Gripping receptacle



June 9, 1936. E L, JR 2,043,247

GRIPPING REGEPTAGLE Filed June 15, 1932 2 Sheets-Sheet 1 June 9, 1936, H. HUBBELL. JR

GRIPPING RECEPTACLE Filed June 15, 1932 2 Sheets-Sheet 2 Patented June 9, 1936 ieu PATENT ori Gairrmo nncnr'rnoan Harveyllubbell, Jr., Bridgeport, Conn. Application June is, 1sag,..seria No. 61mm to Claims. (omits-see) This invention relates to new and useful improvements in electrical connectors such as are used for connecting the leads of electrical appiiances to a source of power, and has for an object to provide an improved connector means adapted to receive any of the, known standard contact blades or fingers of an attachment plug cap and engage said fingers in a manner to prevent casual or inadvertent separation of the cap from the connector means.

Other objects and advantages will become apparent from a consideration of the following detailed description taken in connection with the accompanying drawings wherein a satisfactory embodiment of the invention is shown. However, it will be understood that the invention is not limited to the form or details disclosed, but includes all such variations and modifications as fall within the spirit of the invention and the scope of the appended claims.

In thedrawings:

Fig. 1 is a top plan view of a duplex receptacle in accordance with the invention, an attachment plug cap being shown in place thereon;

Fig. 2 is a side elevational view of the device of Fig. l;

Fig. 3 is a top plan view of the receptacle base, the cover section being omitted;

Fig. 4 is a side elevational view of the cover section of the receptacle;

Fig. 5 is a bottom plan view of the cover;

Fig. 6 is a sectional view on an enlarged scale through the receptacle and cover substantially on the plane of line 6-6 of Fig. 3 and showing a cap in place thereon;

Fig. '7 is a sectional view taken along the line 'i-l of Fig. 6, but showing the parts in locked position; a s

Fig. 8 is a view somewhat similar to Fig. 7 but showing the parts in unlocked position;

Fig. 9 is a side elevational view on an enlarged scale and showing a contact in accordance with the invention;

Fig. 10 is a top plan view of the contact of F 9;

Fig. -11 is an end view of said contact and showing a contact blade or finger of an attachment plug cap associated therewith;

Fig. 12 is a more or less diagrammatic view on a greatly enlarged scale and illustrating the gripping action taking place between the contact fingers of a cap and the contact fingers of the connector member; and

Fig. 13 is a view somewhat similar to Fig. 12

but illustrating a modification.

In the accompanying drawings and in the idl lowing detailed description the invention is illus= trated and described as applied to a stationary duplex receptacle. This is merely for the purpose of illustration and as the description pro ceeds it will become apparent that the invention is equally applicable to single receptacles. to plugs used in flexible connections, to current taps, and the like. Therefore, it will be understood that I do not limit myself to applying the invention to any particular form or type of connector.

Heretofore, electrical connectors including a body member and an attachment plug cap have been provided with means whereby the body and cap might be secured together against accidental separation and with their contacts in engagement. Such structures, however, have always required that the attachment plug cap be provided with a particular construction of contact fingers in order that the locking feature might be used and have not been capable of co-operating with the standard contact blades of an attachment plug cap to lock a cap and body together. Accord ing to the present invention an electrical connecttor, which may take the form of a plug, stationary receptacle, current tap or the like, is provided'with means adapted to cooperate with any of the standard contact blades of an attachment cap or the like whereby to prevent accidental separation of said blades from the contacts of the connector or receptacle. Where the term standard can is used in the specification and claims this is intended to mean a cap having two projecting contact blades parallel to each other of substantially rectangular cross section of sub stantially uniform width and thickness throughout at least the portions intended to engage the contacts of receptacles and connectors except for a transverse opening through them adjacent their free ends. In other words these are the connector caps having contact blades of the size, shape and shown a connector in the form of a duplex receptacle and including a body I 6 of insulating material provided with recesses H for the reception of contacts ill. Since the invention does not particularly relate to duplex receptacles, but one end of the receptacle of Fig. 3 is shown equipped with the contacts l8 although it will be understood that in a completed duplex receptacle both end portions of the receptacle would be equipped with contacts.

The body l6 includes a longitudinally extending rib l9 and projecting upwardly at the sides of the intermediate portion of this rib are extensions 26 and 2| defining a channel at the upper side of the rib. Laterally or the extensions 20 and 2| cover 26 includes sidewall portions 22 and 23 forming shoulders 24 for a purpose to be described. Also, the wall of the body defining the outer side of one of the recesses I1 is appreciably thickened to provide a shoulder 25 the purpose of which will later appear.

Body [6 further includes a cover member 26 formed of insulating material and shaped to fit the body and give a finished appearance thereto. This cover 26 is on its underside provided with a longitudinally extending rib 21 adapted to be received in the channel or space at the upper side of the rib l9 which channel or space is as above described defined by the extensions 26 and 2|. At its ends the rib 21 of the cover is enlarged or formed with heads 28. Arcuate slots or openings 29 are provided in the cover 26 at opposite sides of the heads 28 and these slots are arranged to align with the recesses 11 in the body when the cover is assembled on the body. Any suitable means may be provided for securing the body and cover together and such means may take the form of a screw ill passing through the body and threaded into an-insert 3| in the cover.

The contact members It each include a base or strap member 32 having an upstanding portion 33 to which is connected a binding screw 34 connecting suitable leads 35 with the members. Additionally as here shown each contact member includes inner and outer contact elements 36 and 31 respectively the said contact elements being arranged substantially vertically and at their lower ends being secured by any suitable means, such as rivets for example, to an upstanding portion 36 of the strap or base member 32 as at 39. Additionally the parts may be soldered as shown. It is to be understood that the contact members It may be constructed otherwise than as here disclosed. For example, the members may be bent up from a suitable stamping and thus be formed all in one piece eliminating the riveting and soldering operation referred to.

It will be noted that the contact elements 36 and 31 are preferably transversely curved and are substantially concentric. The upper end portions of these contact elements are extended laterally whereby to provide a lateral extension 40 on each of the elements 36 and a lateral extension 4| on each of the elements 31. The lower edge portion of each lateral extension 4| is turned inwardly to provide a substantially wedge shaped portion or flange 42 the purpose of which will later be fully set forth.

By reference to Fig. 8 it will be noted that when the contact members are assembled in the body the lateral extension 4| of one of the outer elements 3'! is disposed closely adjacent the shoulder 26 of the body and that the corresponding portion of the other contact member is disposed closely adjacent the shoulder 24 of the side wall portion 22 of the cover. Further it will be observed that the head 28 at one end of the rib 21 of the closure is disposed between the inner elements 36 of the contact members and in engagement with or closely adjacent said elements.

. As before explained when the cover 26 is as sembled on the body It the arcuate slots 29 through the cover are aligned with the recesses I! in the body. These slots provide openings for the entrance for the contact fingers or blades 43 of an attachment plug cap 44 whereby said fingers may be moved into engagement with the contact members I8 on a relative longitudinal movement between the cap 44 and the connector l5. When the fingers 43 are passed through the slots 29 the said fingers enter between the contact elements 36 and 31 and engage each of them as best shown in Figs. 7 and 8. This engagement with each of the contact elements is insured by the spring action of the receptacle contacts.

It will be understood that the contact fingers or blades of the cap 44 may be of any or the usual standard construction and that these fingers may be brought into and out of engagement with the elements of the contact members by passing said blades through the slots or openings 29 in the cover 26. This is the usual method of connecting the contact fingers of a cap with the contacts of a receptacle, plug or the like and it will therefore be seen that this improved gripping connector may be used if desired in the ordinary way with the ordinary type of cap equipped with the standard contact fingers.

With the usual construction of connector the contact blades of a cap may be accidentally disconnected from the contacts of a receptacle, plug or the like on a pull being placed on the cord to an appliance. The structure of the present device provides means to prevent this casual or accidental separation of the connector I5 and the cap 44, it being but necessary after the fingers have been passed through the slots 29 to impart a relative turning movement between the connector and the cap 44 whereby to shift the contact fingers 43 of the cap from the positions in which they are shown in Fig. 8 to the positions in which they are shown in Fig. 7. This relative rotary movement causes the contact fingers to engage the tapered flanges 42 of the respective outer contact elements and particularly the sharp edges 41 of said flanges. This turning movement may cause these sharp edges to cut slightly into the contact fingers, but at any rate they are pressed tightly against them and if there is strain put on the cap tending to withdraw it from the receptacle the flanges 42 will have a wedging action against the fingers or blades and grip them harder. The greater the pull, the greater will be the gripping action up to a certain point and it may cause the sharp edge to cut deeper into the blade to give a greater holding effect. This is illustrated in Figs. 11 and 12. It will, however, not be sufilcient to positively lock the cap contacts against withdrawal from the receptacle, as the gripping action is not suflicient to break the leads or to ordinarily pull them from their binding posts. It is intended to be merely sufiicient to prevent accidental pulling of the cap blades from the receptacle under the usualcasual strains on the cord, but to yield under unusually heavy strain so as not to break the leads or other elements.

The contact fingers 43 are usually formed of brass and are softer than the bronze contact members I8. As the fingers are rotated on relative turning movement between the cap and the connector the fingers ride on to the flanges 42 and the greater the relative turning movement between the connector and the cap the farther the fingers will ride onto said flanges. The edges of the flanges are thus pressed tightly against the contact blades. By comparison of Figs. 7

42 gripping tightly the contact fingers 4i, and

may cause them to cut slightly into the surfaces of the fingers. Here it is .to be noted that the head 28 on the rib 21 of the cover prevents yielding movement of the inner contact elements in directions toward one another or away from their respective outer contact elements and the contact fingers are therefore held .firmly against the flanges 42.

After the cap at and the connector l5 have been given a relative turning movement as described, any ordinary accidental strain on the cord 45 from the cap will not result in the separation of the cap and connector. The strain will be resisted as diagrammatically illustrated in Fig. 12 wherein the arrow 46 indicates the direction in which such a strain would attempt to move the finger as. Since the flange d2 of the outer contact element has tightly gripped the finger and its edge may have cut slightly into the linger as suggested at W it will be apparent that the finger may not be pulled longitudinally out of the connector by ordinary strains but .will be bound or gripped by the flange at which will resist pulling out of the fingers and hold them against ordinary strains. The fingers will, however, pull away from the gripping fingers before the pull or strain becomes suilicient to. break the leads or pull them away from the binding posts. The force of the pull will act on the flange M as suggested by the arrow tit and it will be noted that this force tends to press the contact element either against the shoulder 25 or the shoulder 2d of the wall 22 as the case may be. In any event, the force of the pull is directly transmitted to a solid portion of the connector. Obviously, the finger or blade ti may not move away from the flange 42 since the blade is held against movement in such a direction by the inner contact element which in turn is held against movement by the head 28 against which it bears. The contact id is thus wedged and bound or gripped between the flange 42 and con tact 36 by the pull on the finger 53.

From the foregoing description it will be understood that according to the present invention an attachment plug cap may be used with my improved connector either with or without gripping it. That is, if the connector and cap are connected by a simple relative longitudinal movement they may be separated by a similar movement. However, when they are given a relative rotary movement after being connected by the longitudinal movement the contacts of the connector grip the fingers of the cap and the parts are thus held together. In this condition the cap and connector may not he accidentally separated, but when they are to be separated it is only necessary that they be given a relative rotary movement in the opposite direction which movement will result in the contact fingers being carried out of engagement with the inturned flanges M of the contact members. The cap and connector may then be easily separated in the usual manner by a relative longitudinal movement as will be .understood. It is pointed out that the contact fingers and the contact members remain in engagement during the relative rotary movements referred to and arcing is there- & by prevented. The backing up members 38 provide an extended contact surface on the receptacle contacts engaging the cap blade contacts 43 to provide good electrical contact, and therefore it is not necessary to. rely solely on the relativelylimited contact surface of the flanges 42 on the cap blades.

Attention is also directed to the fact that this gripping feature is obtained without a substantial increase in the cost of producing the connectors. The only additional material involved is the lateral extensions on the contact element's 3t and Si and it is the flanges 42 of the latter that give the ripping eilect. The device may be used with the ordinary type of attachment plug cap having the usual straight contact fingers so that no special construction of cap is necessary and the device may therefore be used with the caps at present on the market and yet give the desired gripping edect.

Fig. 13 suggests a slight modification wherein the inner contact elements 36 are provided with inturned flanges 49 corresponding with the inturned tapered flanges t? of the element ti whereby a strain tending to separate the cap and connector will be distributed to the two con= tact elements when the parts are in the gripping position since each element will include a flange which is capable of gripping the contact finger, on the parts, that is, the connector and cap, being given a relative rotary movement. The device suggested in Fig.13 would involve the same oper ations as already described in connection with the other figures of the drawing and further description is therefore believed unnecessary.

Having thus set forth the nature of my invention, what I claim is:

i. In an electric connector, an insulating body having recesses therein and arcuate openings leading to said recesses, contact members in said recesses and including arcuate lateral portions substantially concentric with said openings, a standard can having parallel straight contact fingers insertable through said openings into engagement with the contact members by a relative longitudinal movement between the body and cap, said lateral contact portions comprising gripping means within the body and mounted to grip said contact fingers to resist separation of the cap and body, and said gripping means mounted to become effective'after longitudinal movement of the fingers into engagement with the contact members by a lateral shifting of said contact fingers into engagement with the lateral contact portions while continuously in engagement with the contact members.

2. In an electric connector, a body of insulating material having recesses therein and openings leading to said recesses, contact members in said recesses, a standard cap having parallel straight contact fingers insertable through said openings into engagement with the contact members by a relative longitudinal movement of the cap and body, said openings being of sufiicient length to permit a lateral sliding movement of said fingers on the contact members by a relative turning movement of the cap and body and while said fingers are in their normal relations to each other, and gripping means on said contact members to grip said contact fingers to resist separation of the cap and body in a direction longitudinally of the fingers and mounted to become effective and ineffective by the relative lateral sliding movement of the contact members and contact fingers on one another by said relative turning movements of the cap and body.

3. In an electric connector, 9. body oi insulating material, spaced contacts in said body, said body having openings leading to said contacts and providing entrances for the straight parallel contact fingers of a standard cap, said openings in the body elongated to permit of a longitudinal movement of the contact fingers into the body and into engagement with the contacts therein and then a lateral movement relative to said contacts and while in engagement therewith, and at least one of said contacts within the body including means to engage and bite into a finger on said lateral movement and thereby secure the finger against longitudinal movement out of the body upon a strain being placed on the finger.

4. In an electric connector, an insulating body having recesses therein, contact members in said recesses, said body having openings leading to said recesses, a cap including standard parallel straight contact fingers insertable through said openings on relative longitudinal movement between said body and a cap, said contact members each having a laterally extending gripping portion to engage the fingers oi the cap on relative turning movement of the cap and body after the fingers and contacts have been brought into engagement by a relative longitudinal movement of the cap and body and while constantly in engagement to grip the fingers and solely by said grip to secure the body and cap against separation by a pull tending to separate them in a direction longitudinally of said fingers.

5. In an electric connector, an insulating body member having recesses therein, contacts in said recesses, said body having openings leading to said recesses for the entrance of the parallel straight contact fingers of a standard cap and of a width to permit lateral movement of the fingers while in the openings, each of said contact members having an inturned portion to bite into a finger of said cap to thereby secure the cap and the body against casual separation and becoming effective by said lateral movement, and said body including portions engaging said contact members and supporting them against movement in a direction away from the fingers of the cap.

6. In an electric connector, an insulating body member having recesses therein, contact members in said recesses, said body having openings leading to said recesses for the entrance of the parallel straight contact fingers of a standard cap on relative longitudinal movement between said body and a cap, each of said contact members including a pair of spaced elements adapted to receive a contact finger of said cap between them and engage its opposite sides, said body including portions to prevent spreading apart of the elements of said contact members, and one of the elements of one of said members including gripping means to engage a contact finger of a standard cap on lateral movement of a contact finger of the cap between the elements of said contact member and thereby secure the body and a cap against accidental separation in a direction longitudinally of the finger.

7. In a device of the character described, an insulating body having recesses, a contact in each of said recesses and each including an arcuate portion, said body provided with arcuate slots leading to said contacts and substantially concentric therewith to permit of longitudinal movement of the fingers of a standard attachment plug cap including parallel straight contact fingers into said recesses and then permit a lateral movement of said fingers relative to the body while in said recesses, a tapered flange on one of said contacts, said flange angularly disposed relative to said contact and extending crosswise or its recess, 5 and said flange mounted to grip a contact finger of said attachment plug cap while its fingers are in said recesses to secure the body and cap against casual separation and becoming eii'ective on said lateral movement. 10

8. In an electric connector, an insulating body having recesses therein, an insulating cover for said body and having openings leading to said recesses for the entrance oi the parallel straight contact fingers of a standard cap and 01' a width 15 to permit lateral movement of the fingers while in the openings, a contact member in each of said recesses, each of said contact members comprising a pair oi spaced elements, means carried by said cover and disposed between said contact 20 members and supporting one of the elements of each of them in a manner to prevent the supported elements moving away from their companion elements, said body including portions supporting the said companion elements of said members to 25 prevent them moving away from the cover supported elements, each of said contact members having its elements mounted to receive a contact finger of the standard cap between them and engage its opposite sides, and one of said 30 elements of each of said members including a gripping portion to grip a contact finger of the cap and solely by said-grip to secure the body and cap against casual separation in a direction longitudinally of the finger, said gripping means being mounted to become effective and ineffective by lateral movements of the fingers.

9. In an electric connector, an insulating body having recesses therein, a contact in each of said recesses and each including an arcuate portion, 40 an insulating cover for said body and having arcuate slots leading to said contacts and substantially concentric therewith to permit of longitudinal movement of the parallel straight contact fingers of a standard can into said recesses 45 and then permit a lateral movement of said fingers relative to the body while in said recesses, each of said contact members comprising a pair of spaced elements, means carried by said cover and disposed between said contact members and sup- 50 porting one oi the elements of each of them in a manner to prevent the supported elements moving away from their companion elements, said body including portions supporting said companion elements oi said members to prevent them moving 55 away from the cover supported elements, each of said contact members having its elements mounted to receive a contact finger of the standard can between them and engage its opposite sides, and one of said elements of each 69 of said members including a gripping portion to grip acontact finger of the cap on relative turning movement 01 the cap and body and solely by said grip secure the body and cap against casual separation in a direction longitudinally of 65 the finger.

10. In an electric connector, an insulating body having recesses therein, a contact in each of said recesses and each including an arcuate portion, an insulating cover for said body and having arcuate slots leading to said contacts and substantially concentric therewith to permit of longi-' tudinal movement of the parallel straight contact fingers oi a standard cap into said recesses and then permit a lateral movement of said standard cap between them and engage its opposite sides, a tapered flange on one or the elements of one of said contact members, said flange anguiarly disposed relative to the elements of said member and extending crosswise of its recess,

and said flange mounted to grip a contact finger 01' said cap on relative turning movement of the cap and body while said fingers are in said recesses to secure the cap and body against casual separation in a direction longitudinally of the fingers. 10

HARVEY HUBBEIL, JR. 

